ANAHEIM, Calif. — The Islanders’ power play did everything but score. That is one of the keys to the whole thing, though, and the latest power-play failures cost them.

Their 3-2 loss to the Ducks was a winnable game, the second straight in which the Islanders put more than 40 shots on an opposing goaltender. But John Gibson’s 39 saves didn’t leave the Islanders feeling snake-bitten, just frustrated that there were points available for the taking that they didn’t take.

“You’ve got to score,” coach Doug Weight said of his team’s power play, which was 0-for-5 on Wednesday and is now 0-for-15 this season. “When you’re 4-for-16, 4-for-20, you can look at tonight and say you did some good things, you had some momentum. But we gotta score.”

The Ducks took advantage of a bad first Isles shift to grab the lead 37 seconds in when Jaroslav Halak left a juicy rebound and Andrew Cogliano swept the puck past Halak with no Islanders in sight. But that sequence appeared to awaken the Islanders at the outset of this three-game California swing and they outshot the Ducks 21-4 over the remainder of the first.

Brock Nelson tied it on a deflection of Scott Mayfield’s shot at 13:09 and the Islanders looked to have the game going the way they wanted. They got a power play 33 seconds into the second but didn’t convert, letting the game sit tied until Rickard Rakell deflected Cam Fowler’s shot between Halak’s legs at 8:39 for a 2-1 Ducks lead.

Halak let a stoppable Patrick Eaves shot get through at 5:32 of the third, just 35 seconds after another Isles power play went by, but Nelson pulled the Isles back within a goal at 7:57.

The Ducks appeared to make it 4-2 with 8:35 left in the third when Derek Grant redirected a shot past Halak, but Weight challenged the goal for offside when the Ducks entered the zone 19 seconds earlier.

The Ducks were indeed offside and the goal was taken off the board. Weight had challenged a similar goal on Monday against the Blues and lost that challenge, putting his team two goals and a man down; that was in the second period, however. On Wednesday, so late in the game, it was well worth the close call and it went the Islanders’ way.

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“I think parts of our game are really coming along and there’s obviously some areas we can clean up,” said John Tavares. “It’s four games in so there’s no reason to feel panic or not stick together.”

The frustration is palpable, however. The Islanders have preached getting off to a good start — to the season and in each game — and that early breakdown hurt, as well as a game without getting a point in which they were superior.

“Whether it’s 5-1 or 3-2, it’s still a loss,” Johnny Boychuk said. “We need points because we know how important they are at any time of the year.”

Notes & quotes: Josh Ho-Sang had two assists . . . Cal Clutterbuck (hip) is still not ready to return and missed his third straight game and defensemen Dennis Seidenberg and Ryan Pulock were healthy scratches. Pulock, 22, has yet to play this season, though Weight said, “Pulie will get in. I just decided to stay with this group.”